The acquisition, which will be the largest overseas purchase by a Japanese company, has already received unconditional clearance from U.S. and Brazilian regulators and awaits approval from Japan and the European Union.

Takeda expects the deal to close in the first half of 2019.

Its shares ended 0.7 percent higher ahead of the announcement. The benchmark Nikkei 225 index closed up 1.2 percent.

Takeda's stock is down 15 percent since the company first said it was considering a bid for Shire, with investors concerned about the heavy debt burden the deal will impose on the drugmaker.

(Reporting by Shashwat Awasthi in Bengaluru and Sam Nussey in Tokyo; Editing by Sai Sachin Ravikumar)